For physicians and medical professionals, accessing systems for vessels and bodily cavities in patients have typically used various guidewire and catheter technologies. In some cases, the process requires the insertion of a series of mandrels or wires to increase the lumen diameter for the eventual passage of a larger bore instrument within the vessel. This technique can be referred to as “Dottering” or in the case of accessing the cervical canal and uterus, physicians will use a series of increasing diameter mandrels known as Hegar dilators. In the techniques described above, the methods involved pushing an object, mandrel, or device through the vessel to gain access to a desired region in the body. The result of pushing an object, mandrel, or device creates shear forces on the lumen wall. In some cases the shear forces can result in trauma, pain for the patient, or perforation.
In contrast, another access technology that has been used in prior an is referred to as an everting catheter. Everting catheters utilize a traversing action in which a balloon is inverted and with the influence of hydraulic pressure created by a compressible or incompressible fluid or media, rolls inside out or evens with a propulsion force through the vessel. Everting balloons have been referred to as rolling or outrolling balloons, evaginating membranes, toposcopic catheters, or linear everting catheters such as those in U.S. Pat. Nos. 5,364,345; 5,372,247; 5,458,573; 5,472,419; 5,630,797; 5,902,286; 5,993,427; 6,039,721; 3,421,509; and 3,911,927; all of which are incorporated herein by reference in their entireties. These are categorized as evening balloons and are for traversing vessels, cavities, tubes, or ducts in a frictionless manner. In other words, an everting balloon can traverse a tube without imparting any shear forces on the wall being traversed. Because of this action and lack of shear forces, resultant trauma can be reduced and the risk of perforation reduced. In addition as a result of the mechanism of travel through a vessel, material and substances in the proximal portion of the tube or vessel are not pushed or advanced forward to a more distal portion of the tube or vessel.
In addition, as the everting catheter deploys inside out, uncontaminated or untouched balloon material is placed inside the vessel wall. In the inverted or undeployed state, the balloon is housed inside the catheter body and cannot come into contact with the patient or physician. As the balloon is pressurized and everted, the balloon material rolls inside out without contacting any element outside of the vessel. Another advantage of an everting balloon catheter is that the method of access is more comfortable for the patient since the hydraulic forces “pull” the balloon membrane through the vessel or duct as opposed to a standard catheter that needs to be “pushed” into and through the vessel or duct.
The method typically used by physicians for accessing the cervical canal in women requires the use of multiple instruments of increasing diameter. The physician will use a small uterine sound or small diameter probe or Hegar device for gaining initial entry into the uterus via the cervix. Ever increasing sizes of Hegars are used to stretch the cervical muscles until the desired internal diameter is achieved for the insertion of a secondary instrument such as an endoscope or other device. This process can be particularly difficult in some nulliparous, post-menopausal women with very small diameter cervical canals. A cervix could be difficult to traverse as a result of prior surgery, underlying stenosis, or other anatomical configuration or tortuosity that makes the passage of instruments or Hegar dilators difficult.
There are some cervical dilators that provide radial expansion to open the cervical canal to a greater internal diameter without the insertion of multiple instruments. All of these devices are predicated on first crossing or traversing the cervical canal prior to the step of radial expansion. Once traversed through the cervical canal, these devices use either mechanical means or the expansion of a balloon dilation member that is concentric on the exterior of the dilator probe. If the cervical canal is particularly tight or narrow, a small diameter probe or mandrel may be required to first cross the cervix and access the uterine cavity. As mandrels or instruments get smaller in diameter, the likelihood of perforation or a false passage increases. In any case, these cervical dilators require passage or crossing by the initial probe prior to any further radial expansion being performed.
Everting catheters have been described as dilatation catheters. Representative examples of dilating everting catheters include U.S. Pat. Nos. 5,364,345 and 4,863,440, both of which are incorporated by reference herein in their entireties.
Everting catheters have also been described with additional elements such as a handle for controlling instruments within an everting catheter. A representative example is U.S. Pat. No. 5,346,498 which is incorporated by reference herein in its entirety. Everting balloon catheters can be constructed with an inner catheter with an internal lumen or through-lumen (or thru-lumen). The through-lumen can be used for the passage of instruments, media, materials, therapeutic agents, endoscope, guidewires, or other instruments. Representative samples of everting catheters with through-lumens are in U.S. Pat. Nos. 5,374,247 and 5,458,573. In addition, everting catheters have been described with waists or a narrowing of the balloon diameter, such as in U.S. Pat. No. 5,074,845, which is incorporated by reference herein in its entirety.
Furthermore, infertility is a condition that affects 1 out of 8 couples in the US. One of the early treatments in the infertility regime is insemination. Intrauterine insemination or IUI is a very common procedure since it is in the early work up of an infertile couple. Most assisted reproductive clinics perform at least 3 IUI cycles before trying more expensive treatment options such as IVF. IUI cycles may be coupled with drugs to stimulate greater ovulation to improve the chances or likelihood of pregnancy. Sperm that is collected from the male is typically washed and prepared prior to an insemination through a catheter with the goal of providing a greater volume or amount of viable sperm in the uterine cavity and into the reproductive tract of the female.
As part of increasing the odds of getting pregnant, physicians have been using a variety of means of increasing both the amount of sperm and the duration sperm could be in the uterine cavity. To keep sperm from exiting the cervical canal after insemination, physicians have used rubber and silicone based cervical caps that are designed to fit over the exocervix as a sealing member. In practice, a physician will either inseminate the uterine cavity or fill the cervical cap with sperm and then fit over the cervix as a seal. The security of the cervical cap is not reliable and due to its size and bulk, not as comfortable for the patient. Typically a cervical cap will only be used by the patient within the physician's office for a predetermined amount of time. The overall objective of the cervical cap is to keep sperm in the uterine cavity for as long as possible without being expelled or spilling from the cervix due to gravity or contractions of the uterus. Ideally the sperm will migrate upward through the fallopian tubes to the fimbria where conception can occur if an oocyte from an ovary is present. Many clinical investigations have reported that, once through the fallopian tubes, sperm can travel throughout the peritoneal cavity and stay viable for many hours in situ. Equally, sperm can stay viable in a controlled environment or an incubator for many hours.
Another methodology for keeping sperm in the uterine cavity is done by use of a pump connected to a catheter within the uterine cavity. A pump that can be worn by the women or keep bedside is filled with sperm and is pumped through the catheter at a rate pre-set by the physician. For instance, the pump can be set to run for 2 to 6 hours at which sperm is pumped through the catheter and into the uterine cavity. The pump can be worn by the woman outside of the physician's office but patient mobility is limited due to keeping the integrity of the conduit and pump.
Also, when delivering the reproductive material, such as an embryo, into the uterine cavity, vacuum effect can unintentionally remove the reproductive material from the uterine cavity. In existing systems, when the transfer catheter is retracted from a second outer or guiding catheter (e.g., the “inner” catheter), the retraction produces vacuum pressure within the uterine cavity. This vacuum pressure is created in the uterine cavity by the removal and backward movement of the transfer catheter within the inner catheter. After the embryo transfer is completed, an embryologist may inspect the transfer catheter to verify that the embryos or reproductive material was indeed deposited in the uterus and not pulled back into the transfer catheter because of the vacuum effect. The same procedure may be done for the outer catheter once this catheter is removed.
Further, incontinence is a prevalent clinical and social issue that primarily affects women. Various publications estimate the percentage of women with urinary incontinence from 15 to 30% in the over 60 age group. The amount spent treating incontinence ranges from $3 to 5 B annually in the US. Urinary Incontinence is one of the 10 most common chronic conditions in the US with over 15 M women diagnosed in the US alone. Most feel that this number is under-reported. The choice of therapeutic options has limited reimbursement and many of the techniques lack consistent data. As an example, invasive approaches in women include suspensions of the bladder neck, collagen injections, and RF remodeling. Incontinence is a multi-factorial disease condition and patient satisfaction with many invasive techniques is poor. For patients, surgery is the last preferred resort. Noninvasive techniques include biofeedback and Kegel exercisers. These techniques improve the muscle tone in the patient's pelvic floor but they rely on patient compliance to be effective. Less invasive options involve mechanical pressure devices such as pessaries, urethral catheters or inserts, and patches over the urethral opening. Most incontinence money is expended on purchase of absorbent products. Due to the social stigma, many patients are reluctant to seek advice and many patients decline surgical and less invasive options. Consequently, male and female incontinence patients rely on sanitary pads and the restrictions that the presence of bulky, wet pads imposes on their daily lives.
In some patients, a urethral insertable device for sealing is the preferred method for managing their incontinence. These inserts are designed for single use and are self-applied. Typically they rely on the measurements of urethral length for insertion and balloon inflation.
Urethral inserts are plugs that typically incorporate a balloon mechanism to create a seal in the urethra or bladder. For voiding, the balloon is deflated. These devices have been described previously in the art including U.S. Pat. Nos. 5,090,424; 5,483,976; 5,724,994; 5,752,525; and 5,769,091 all attributed to Simon et al. Additional art is found in U.S. Pat. Nos. 5,806,527; 6,449,060; 6,926,708; EP 0900058 B1, and EP 1365713 B1. U.S. Pat. No. 5,927,282 to Lenker et al describes an adhesive patch for covering and sealing the urethral opening and sealing the external opening to the urethra.
Further art includes U.S. Pat. No. 5,662,582 which describes an evening urethral plug with an invaginating balloon mechanism. Everting balloons describe an action in which a balloon is inverted and, with the influence of hydraulic pressure created by a compressible or incompressible fluid or media, rolls inside out or everts with that propulsion force. Evening balloons have been referred to as rolling or outrolling balloons, evaginating membranes, toposcopic catheters, or linear evening balloons. These are all categorized as everting balloons due to their property of traversing vessels, cavities, tubes, or ducts in a substantially frictionless manner. Everting balloons can traverse a tube without imparting any significant shear forces on the wall being traversed. Because of this action and lack of shear forces, material and substances in the proximal portion of the tube or vessel are pushed or advanced forward to a more distal portion of the tube or vessel. For example for urethral everting balloons, potentially infectious substances from the vagina, urethral openings, or the hands of the patient, are not in contact with the everted balloon that resides in the urethra. In contrast, urethral plugs and inserts in use currently have a propensity of urinary tract infections which may be a result of the lack of cleanliness of the device that resides in the urethra or bladder.
This methodology would be more widely adopted if the inserts were more comfortable while wearing, had less of a foreign body sensation, and were easier to use or insert. More significantly, many patients who are insert users complain of higher incidence of urethral infection and soreness at their urethra and groin region, especially with increased activity, which is the ideal time the user would want the insert to operate properly.
For a patient, being able to insert a device within their own urethra is not easy and the act itself is unnatural for the patient. Training by a nurse or physician is required for a patient to master the technique. Since the inserts used today require pushing a device through the urethra, the urethral passageway could become sore or tender after repeated insertions.
Current urethra inserts are typically sized to match the length of the patient's urethra, not as a “one size fits all.” Current inserts need to create a balloon seal at the bladder coupled with a compressive force at the urethral opening. Thus the insert length is calculated by sounding the length of the urethra by a probe or via ultrasound measurement. The calculation is designed to hold the balloon taut against the opening of the bladder and the compressive force of the external portion of the insert of the opening of the urethra. Hence it is understandable that the presence of a relatively stiff device that is keeping the opening of the bladder tight against the urethral opening can create an uncomfortable feeling for the patient, especially a patient that is active and mobile.
Furthermore, urinary protection and voiding could occur 3 to 7 times a day, a high cost device would not be acceptable to most patients or would limit the device usage to only the most socially challenging events.